How and why to make seedbombs

Fun and easy to make, seedbombs can be used to green up hard-to-access urban wasteland or in your garden at home

Seedbombs originated in seventies New York. The term was originally 'seed grenade' and comprised wildflower seeds, water and fertilizer all wrapped up in a condom. They were lobbed over fences onto empty lots, with the overarching aim of making neighbourhoods sprucer.

From these small beginnings grew the guerilla gardening movement itself, where vacant lots were turned into productive community gardens with vegetables and edible flowers on tap.

However, seedbombs are not just for guerilla-style gardening - they can also be used for planting at home. And thankfully, the art of making seed bombs has moved on since the seventies.

Josie Pearl Jeffery, who runs Seed Freedom, a Sussex-based company that specialises in seedbomb kits, holds workshops at gardening events and summer festival.

'Seedbombs have the protection provided by the outer coating of earth and clay and as such the seeds are less likely to be damaged by harsh weather conditions and eaten by insects, birds and rodents,' she says.

The seeds therefore have a better chance of germinating and growing into mature plants - which means fewer seeds are required because the rate of success is higher.

So that's the reasoning behind it, but what's the method?

How to make a seedbomb

Having attended one of Josie's workshops I can tell you how the seed bombs take shape:

1) Mould your clay and compost mixture with water until it is sticky.

2) Add your seed mixture, which can be salad or mixed wildflower seeds, for example, and then pat gently into a small ball around the size of one you'd use for ping-pong.

3) Once you have chosen an appropriate site you can push your ball into place - in a pot/a wall/window box etc.

4) Then ensure it is kept warm (try to avoid frosts) and moist with regular watering until the seeds start to germinate.

If you prefer to adopt the guerilla gardening approach and throw the seedbomb onto some derelict land what will happen?

Josie explains that there are two different outcomes which depend on the weather. The seed bomb will either keep its form and the seeds germinate and sprout from the ball and work their way out of it in time, or if it rains a lot the seedbomb dissolves and seeds will lie on the bare earth until they germinate either on the surface of the ground or get trampled.

'The former is preferable [as there's greater chance of success] but either way the seedbomb is an efficient carrier for the seeds because if you were just to throw a handful, the wind would take them,' she says.

Historical roots

The seedbomb method has been used for centuries with some of North American First Nations' tribes using a variation on the theme. In the east, in ancient Japan they were called 'Earth Dumplings', and were later reintroduced by the Japanese microbiologist, Masanobu Fukuoka (famed author of the classic One Straw Revolution).

Fukuoka was a pioneer in the world of sustainable agriculture by initiating just such 'natural farming' methods. With seedbombs you can create fields of food crops and meadowland and even replant areas that suffer from drought or forest fire damage.

In the urban environment seedbombs are used by guerrilla gardeners to green up wasteland, roadsides, gardens, allotments and window boxes. They are certainly a whole lot easier to deal with than scaling fences armed with plants, spades and compost.

And of course throwing a seed bomb into a public arena can be seen as political statement - a way of expressing the freedom to manage our own environment responsibly, rather than just dutifully using the spaces that are allocated us or come attached to our homes.

They're also fun to make. Josie Pearl Jeffery, who has been been seedbombing for two years, says it was because of people's response that she started running workshops.

'I just loved seeing people as fascinated as I am about seedbombs. I think it's because they're so different to the usual way of seed distributing that draws people's attention. When you make them it's a process of lots of different stages which encourages focus and concentration and is really relaxing.'

Plus, when people are making them it gives her a chance to talk about the history of seedbombs and their uses, the seeds and how to care for them as plants.

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